George ii



(No Model.)

2 Sheets-Sheet 1.

G. H. POOR.

VALVE FOR FLUID PRESSURE BRAKE-S.

5 P M it a Hill I II II J 1 vWNW I f z t a a v i n W W W l l MH mug.

NH w 4%. PETERS. mwmm n m. Wuhirlgtnn. u. a

(No Model.) 2 Sheets-Sheet 2 G. H. POOR VALVE FOR FLUID PRESSURE BRAKES.

No. 396,171. Patented Jan. 15, 1889.

iya

A UNITED STATES PATENT OFFICE.

GEORGE H. POOR, OF ST. LOUIS, MISSOURI, ASSIGNOR TO THE AMERICAN BRAKE COMPANY,

OF SAME PLACE.

SPECIFICATION forming part of Letters Patent No. 396,171, dated January 15, 1889. Application filed August, 21, 1888. Serial No. 283,830. (No model.)

To aZZ whom it may concern:

Be it known that I, GEORGE H. POOR, a citizen of the United States, residing at St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Valves for Fluid-Pressure Brakes; and I hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, wherein Figure 1 is a sectional view of a valve embodying my invention, an auxiliary reservoir and cylinder, and an elevation of a portion of the train-pipe and branch pipe leading to the auxiliary reservoir, showing the arrangement of my valve with relation to the other devices of the system. Fig. 2 is a section of the valve on the line 00 a, Fig. 1. Fig. 3 is a section on. the line y 1 Fig. 1. Fig. 4 is an enlarged central section of the valve, the same as shown in Fig. 1.

Like letters and figures refer to like parts wherever they occur.

My present invention relates to the construction and manner of operating air-valves for fluid-pressure brakes, and has for its object to produce a simple and efficient valve to be operated directly from the train-pipe by slight variations of pressure in said trainpipe; and it consists, mainly, in combining with the valve a diaphragm or impulse chamber, said chamber adapted to be charged through the auxiliary reservoir, andhaving a reducing-valve or like means whereby the pressure in said diaphragm-chamber may be maintained at a given pressure above that of the train-pipe, so as to definitely graduate the increase of pressure in the trainpipe which is required at any time to release the brakes. There are minor features of invention embraced in the particular construction of the devices, all of which will hereinafter more fully appear.

I will now proceed to describe the invention more specifically, so that others skilled in the art to which it appertains may apply the same.

In the drawings, 'l indicates the train-pipe; M, a branch leading therefrom to the diaphragm-chamber or impulse-chamber; m, the branch leading to the auxiliary reservoir, and

for which a suitable valve, 7, is provided.

through which the reservoir is charged, said branch being provided with a suitable checkvalve, 02, opening toward the reservoir; R, the auxiliary reservoir; 0, the passage leading from the reservoir to the valve; 1), the passage 5 5 leading from the valve to the cylinder, and

S the cylinder provided with its customary piston and piston-rod, all of which may be of any desired or well-known character..

The valve has a shell composed of several sections, one of which, A, is provided with a port or passage, 1, for communication with the auxiliaryreservoir R, and a port or passage, 2, for communication with the cylinder S, said ports being separated by the partition 3, in which is the valy'eport l, having a suit-, able seat for a valve, which controls said port In the wall of the shell-section A and in line with valve-port l is the exhaust-port (3,

The valves 5 and 7 are so secured to one and the same stem, 8, that a li mited movement of the stem will seat one and unseat the other, and, if desired, the valve 5 may be formed with the stem and the valve 7 secured adjust ably'by a nut, 9, both valves being faced in any manner well known to those skilled in the art. I

The valve-stcm 8 projects through ahollow post,']0, secured to the section A of the shell and projecting into section B of the shell, the stem 8 having an elongated slot, ll, through which, and also through the post 10, passes a pin, 12, to prevent the rotation of the stem.

The stem R need not he more than an ordinary workmanlike fit in the hollow postlO, as the leak will permit the diaphragm-chamber to lill from the auxiliary reservoir and to equalize with the reservoir when the brakes are off and the valve 5 in the position shown 0 in the drawing but as it may be desirable to prevent any leakage from the diaphragmchamber when the brakes are applied the valve 5 is preferably made a double-seated valve, as shown at 13, and aseat, 14, is formed on the under side of hollow post 10. V

B indicates a second shell-section adapted to inclose the hollow post 10 and form with cap (I a diaphragm or impulse chamber, 1 5, the cap C having a port, 16, by which it commu- IOO nicates with the train-pipe.

17 indicates a disk havinga hollow threaded stub, 18, and a hollow stem, 19, within which is a check-valve, 20, that opens away from the diaphragm or impulse chamber 15 and toward the train-pipe 10. This check-valve 20 is weighted by a spring, 2], of any desired force, which converts it into a reducing-valve,which can be graduated so as to maintain the pr( sure in the impulse-ehambcr 1? at any degree above that in the train -pipe, so that such increase of pressure in the train-tape will. release the brakes. lt,theretore,the power of spring 21 be one pound, the reduction-valve will nntintain the pressure in impulse-chamber15 that much above the pressure in the train pipe, and an increase of one pound t pressure in the train-pipe will seat the valve on the port -land unseat the exhaust-valve 7, releasing the brakes.

22 indicates a port in the hollow stem 15) for establishing the communication between reducing-valve 2t) and. the impulse-chamber 23 is an annular disk, between which and the disk 17 the diaphragm El isclamped.said diaphragm being also clamped between the shellseetion ll and the cap and the stem 19 is connected with stem 8, so that the dia-i phragm 24 directly controls valves 5 and 7.

tially as hereinbeli'ore specified, will operate as follows: The system being charged, with at r at the desired pressure, the air will pass to the reservoir directly by branch '11 and through passages o I, and the leak through.

For purposes of convenience l. have illustratcd the invention as applied by means of a diaphragm and the reduction-valve as arranged in a hollow stem passing through the diaphragm; but itwill be evident to any skilled mechanic that a piston can be substituted for the diaphragm and that the reduction-valve can be placed in a passage leading around instead of through the diaphragi'n, which will be equivalents for the construction shown and embraced by the claimshereinai'ter made.

Having thus described the nature, advantages, and operation of my inventioi'i, what I claim, and desire to secure by Letters Patent,

l. In a valve for fluid pressure brakes, the coml'iination, with the inlet and exhaust valves, of an impulse-chamber which communicates with the auxiliary reservoir, a diaphragm which is arranged in the impulsechamber and connected with the valves, and a reduetion-valve arranged in apassageleading from the impulse-chamber to the trainpipe, substantially as and for the purposes specified.

2. In a valve for fluid-pressure brakes, the

7 eombiimtion ot' the inlet and exhaust valves The devices, being constructed substanpost 10 around stem 8 will charge the diaf phragm or impulse chamber .15.

It, now, the

pressure be slightly reduced in the trainpipe T, the expansion of the air in im 'mlse-chamber '15 will impart an impulse to diaphragm ill, which will lift valve 5, unclosing port l,

and at the same time seat valve 7, closing ex- I haust-port ti, and thus establish a direct communication between auxiliary reservoir R and the reduction-valve will open and allow;

If the 1 having a stem common to both, an impulseehaml'ler which communicates with the auxiliary reservoir, a dia ilhragm arranged in the impulse-chain])er, and a reduction-valve interposed between the impulse-chamber and the train-pipe, substantially as and for the purposes specified.

13. In a valve for fluid-pressure brakes, the combination of an exhaust-valve, a double,- seated inlet-valve, an im pulse-ch amber, a leak leading from the impulse-chamber to the resa ervoir, said leak arranged to be closedby one face of the double valve, and a reduction valve interposed between the impulse-chambeer and the train-pipe, substantially as and for the purposes specified.

4c. In a valve for fluid'pressure brakes, the combinz'ttion of shell-section A, having passages 1 and 2 and ports l and t3, valves 5 and the air to escape from the impulse-chamber into the train-pipe until the difference ot" pressure is only equivalent to the force of spring E21, when the red uet-ion-valve will close, and when the pressure is subsequently raised in the ti'ain-pi 'ie to release the brakes an increase of even less than the power of spring 21 will, on account of difference in area, i1npart a reverse impulse to tliaphragm 24, thus forcing valve again on its seat, closing port -t, and forcing valve 7 off its seat, opening the exhaust-port I thus releasing the brakes,

7, connected by stem 8, hollow post 10, impulse-chamber 15, a diaphragm having a hollow stem, and a reduction-valve arranged in the hollow stem of the diaphragi'n, substantially as and for the purposes specified.

In testimony whereof I attix my signature, in presence of two witnesses, this 26th day of July, 1888.

GEORGE ll. POOR.

\Vi tnesses:

JNO. R. \VILLIAMS, Jena (7,. H. STEvENsoN. 

